H3C S7500E Series Operation Manual page 358

Operation Manual – IPv4 Routing
H3C S7500E Series Ethernet Switches
Chapter 4 IS-IS Configuration
When configuring IS-IS, go to these sections for information you are interested in:
IS-IS Overview
IS-IS Configuration Task List
Configuring IS-IS Basic Functions
Configuring IS-IS Routing Information Control
Tuning and Optimizing IS-IS Network
Displaying and Maintaining IS-IS
IS-IS Configuration Example
Note:
The term "router" in this document refers to a router in a generic sense or an Ethernet
switch running routing protocols.
4.1 IS-IS Overview
Intermediate System-to-Intermediate System (IS-IS) is a dynamic routing protocol
designed by the International Organization for Standardization (ISO) to operate on the
connectionless network protocol (CLNP).
The IS-IS routing protocol has been modified and extended in RFC 1195 by the
International Engineer Task Force (IETF) for application in both TCP/IP and OSI
reference models, and the new one is called Integrated IS-IS or Dual IS-IS.
IS-IS is an interior gateway protocol (IGP) used within an Autonomous System. It
adopts the Shortest Path First (SPF) algorithm for route calculation.
4.1.1 Basic Concepts
I. IS-IS terminology
Intermediate system (IS). An IS, similar to a router in TCP/IP, is the basic unit in
IS-IS protocol to generate and propagate routing information. In the following text,
an IS is a router.
End system (ES). An ES refers to a host system in TCP/IP. ISO defines the ES-IS
protocol for communication between an ES and an IS, therefore an ES does not
participate in the IS-IS process.
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Chapter 4 IS-IS Configuration